Saturday, November 20, 2004, 7:03:53 PM, Steven wrote: SC> On Sat, 2004-11-20 at 18:48 +0100, Tamas J wrote: >> Hello! >> >> I would like to know wether it is possible to have end-to-end codec >> negotiation in iax2? >> What I mean is... >> >> In case the user dials a number available through PSTN, let's force to >> use alaw (the client is in LAN) to overcome unneeded transcoding: >> iaxphone->1st asterisk -> PSTN >> >> In case the same user dials a number available throug a chain of IAX2 >> peers (e.g. 2 peers), try to negotiate the codec end-to-end to consume >> less resources for transcoding on asterisk servers (of course, in that >> case we don't want to use g711, but ilbc, speex or gsm). >> iaxphone->1st asterisk->2nd asterisk->PSTN >> Or maybe: >> iaxphone->1st asterisk->2nd asterisk->iaxpohone >> >> Is there a way to do that? If yes, how?
If 1st asterisk ->> 2nd asterisk is a link that If 1st asterisk ->> negotiates the ILBC, gsm, SC> or speex, when the call transfers, it should negotiate the codec. Of SC> course part of the interesting effect here is that unless there is NAT SC> or something similar in the way, IAX is going to try and get out of each SC> section if it can. So you may end up with the end result being iaxphone ->> iaxphone and they might be negotiating with each other. Thanks for the fast response! Yes, when the call is transfered, it's logical that parties can negotiate codecs. However is there a way to negotiate end-to-end without call transfer? Is it possible to make this? iaxComm -> asterisk -> E1 PSTN +------> IAX operator When the softphone dials to local PSTN number, let's choose alaw or ulaw codec (to avoid speex/ilbc/gsm -> alaw/ulaw transcoding) and if the call goes out through IAX, let's choose low bandwidth codec (there should be a preferred one, e.g. softphone and iax trunk use speex). What I would like is to avoid unneeded transcoding and save on CPU resources. What I tryed is to put for sofphone: disallow=all allow=speex allow=alaw allow=ulaw When the call went to PSTN it used speex. How can I tell to asterisk to use alaw (or ulaw while iaxComm looks not supporting alaw) in this case? I guess when I would exchange the order and put speex to the and, it will chose ulaw (oops, I tryed and it selected Speex again), but in this case who will do g711<->speex? What is my goal with this? I would like to encode to speex at the softphone's side, thus I can save CPU power on asterisk box. (and if I put 10-20... more softphones, I won't run out with CPU, because when it comes to local call, there won't be transcoding either and when it will go out to iax peer, it will just pass-through). Any idea, hint? Thanks in advance, Tamas ps: sorry for the possible a newbie or/and dumb question... _______________________________________________ Asterisk-Users mailing list [EMAIL PROTECTED] http://lists.digium.com/mailman/listinfo/asterisk-users To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users